下列文中共有10处语言错误，要求你在错误的地方增加、删除或修改某个单词。

增加：在缺词处加出加一个漏字（^），并在其下面写上该加的词。

删除：把多余的词用斜线（\）划掉。

修改：在错的词下划一横线，并在该词下面写上修改后的词。

注意： 1. 每处错误及其修改均仅限一词；

2．只允许修改10处，多者(从第11处起)不计分。

In recently years，dust storms take place more and more often in the north of Chinese. They have brought a great deal of trouble to people’s lives．The strong wind blows up the dust，made the air very dirty. It also stops many of people from going out. In past, people raised a large number of sheep. The sheep eat up a great deal grass and the land became sandy. Now the government have begun to pay attention to the problem. Each year, a lot of  money spent on the improvement of the environment． 

北京人所处时期为原始社会晚期的氏族公社，而山顶洞人所处的时期则是原始社会的早期。